1. Field of the Invention
The present invention generally relates to systems and methods for analyzing differential signal paths, and more particularly to a system and method for analyzing length differences in differential signal paths.
2. Description of Related Art
With the continuing technology advancement of computer systems, high-speed serial signals transmitted between components of the computer systems are essential in the computer systems. As schemes of transmitting high-speed serial signals with accurate time-oriented sequential controls are introduced, the differential signal paths have attracted attention. Each differential signal path is a scheme using a pair of signals whose phases are inverted from each other, and includes a first signal path S+ and a second signal path S−. In this scheme, binary serial data of “1” and “0” are transmitted as a phase-inverted signal pair.
Ideally, the first signal path S+ and the second signal path S− should have an equal length, and at a shortest possible distance away from each other. However, the first signal path S+ and the second signal path S− designed for a printed circuit board (PCB) do not have an equal length and the distance between them are not the shortest distance possible. That is, length differences between the first signal path S+ and the second signal path S− of the differential signal paths are inevitable. More attention must be paid to the length differences between the first signal path S+ and the second signal path S− of the differential signal paths before the differential signal paths are utilized.
Presently, people analyze the length differences between the first signal path S+ and the second signal path S− of a differential signal path by way of comparing the whole length of the first signal path S+ and the second signal path S− one with each other. However, the differential signal path must pass through impedance division positions such as, positions for configuring passive components and positions for configuring vias, which show impedance discontinuity. That is, the error of the length difference analyzed by people is huge.
What is needed, therefore, is a system and method that can be utilized to analyzing length differences between the first signal path S+ and the second signal path S− of differential signal paths, that can overcome the above-described problems by dividing the differential signal paths into a plurality of segments by impedance division positions, so as to accurately analyze length differences of the divided segments.